Invalid walker



June 3o, 1970 A, A SMITH 3,517,677

INVALID WALKER Filed Jan. 21, 1969 2 Sheets-Sheet 1 Arran/ver;

June 30, 1970 A. A, sMlTH 3,517,677

INVALID WALKER Filed Jan. 21, 1969 2 Sheets-Sheet .2l

United States Patent O 3,517,677 INVALID WALKER Alfred A. Smith, 13114 Margate St., Van Nuys, Calif. 91401 Filed Jan. 21, 1969, Ser. No. 793,930 Int. Cl. A61h 3/06 U.S. Cl. 13S-45 7 Claims ABSTRACT OF THE DISCLOSURE An invalid walker comprises two side frames interconnected by a front frame, each of the two side frames forming the two side legs of the walker, each side frame including two lateral members that interconnect the two side legs at different levels, said two lateral members being integral extensions of the front frame. The front frame narrows centrally in crosss ection to form. a torque portion that permits slight relative rotation of the two side frames in their planes for self-leveling of the walker.

BACKGROUND 'OF THE INVENTION An invalid walker of the general type to which the invention refers may be broadly described as comprising a pair of side frames forming the four legs of the walker and a front frame that interconnects the two side frames in a substantially rigid manner. The invalid walkers of this character are disclosed in the following patents:

Blewitt et al., 1,448,783; Thieman, 2,627,904; Ries, 2,759,525; Frank, 2,798,553; Diehl et al., 2,866,495; Ries, 2,996,070; Ries, 3,165,112; Ingalls et al., 3,195,550; and Kempel, 3,279,567.

The present invention meets certain deciencies and needs for improvement in the prior art invalid walkers.

One need for improvement is to achieve a suitable balance between the requirement for substantial rigidity of the two side frames relative to each other and the conicting requirement of yieldability of the two sides relative to each other for self-leveling action of the invalid walker in response to the imposed weight of the user. To make the invalid walker stable and to give the user conlidence in the invalid walker the four legs of the invalid walker should rest simultaneously on a flat floor surface or at ground surface and must accommodate themselves as well to irregularties in a oor surface or ground surface.

Although the invalid walker must have a certain degree of yieldability to accommodate itself to different sup- -port surfaces, nevertheless the accommodation must not be accomplished by relative movement at the joints of the walker structure because the user readily senses any play at the joints and too often has a feeling that the relative motion is'not suiciently limited. A further need Yfor improvement in this respect is to provide an invalid walker construction in which the joint connections are Vnot solely depended upon for the rigidity of the structure.

While the self-leveling capability of the invalid walker requires freedom for at least a slight degree of rotation of the two side frames relative to each-other in their planes, nevertheless the users confidence in the invalid walker requires that the front frame effectively side sway on the part of the two side frames.

A further need for improvement is to align the two side frames of the invalid walker with the downwardly extending -arms of the user.

A further pressing need for improvement is to provide an invalid walker structure that meets the above requirements and yet is simple of construction and inexpensive to produce.

The present invention meets all of the above mentioned needs for improvement.

ICC

SUMMARY oF THE INVENTION The preferred embodiment of the invalid walker construction taught by the present invention comprises essentially four elongated members of U-shaped configuration. Each of two of the U-shaped members is of inverted U-shape, each forming an upper hand grip on one side of the walker and two downwardly extending legs on one side of the walker. The two downwardly extending legs on each side of the walker are interconnected at different levels by two lateral side members, the two lateral side members cooperating with the two legs to form the corresponding side frame of the walker.

The front of the walker is integral with the lateral side members of the two side frames of the walker and thus interconnects the two side frames in such manner as to effectively maintain a given orientation of the two side frames relative to each other. The front frame is in effect wrapped around the front and sides of the walker.

The front frame of the walker comprises two elongated members that are U-shaped in plan, forward intermediate portions of the two members forming the front frame proper and rearwardly extending legs of the two members forming the above mentioned lateral side members of the two side frames.

It is contemplated that while the front frame effectively maintains the orientation of the two side frames relative to each other, nevertheless the front frame yields in torque as may be required to permit the self-leveling adjustment of the walker as required by different support surfaces. For this purpose the front frame narrows centrally to a mid region where the two members of the front frame are contiguous to each other and are interconnected to form what may be termed a torque portion of the front frame that yields in torque for the desired self leveling action.

In one embodiment of the invention the two members of the front frame cross each other at their centers and are interconnected at their intersection to form the desired torque portion of reduced cross section. In a second embodiment of the invention the front frame comprises an upper transverse member and a lower transverse member both of which are offset centrally to converge towards each other and the two offset portions are centrally interconnected to form the torque portion of the front frameQIn a third embodiment of the invention, the front frame comprises a substantially straight upper member and a lower member that is centrally offset upwards towards the upper member and is centrally connected to the upper lmember to provide the desired torque portion of the front frame. v

The features and advantages of the inevntion may be understood from the following detailed description and the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS In the drawings, which are to be regarded as merely illustrative: Y

FIG. 1 is a perspective view of the iirst embodiment of the invalidvwalker with a user indicated inV phantom; FIG. 2 is a front elevation of the invalid walker; FIG. 3 is a top plan view of the invalid walker; Y

FIG. 4 is a side elevational view of the invalid walker; FIG. 5 is a fragmentary sectional view taken along the line 5-5 of FIG. 4 showing how the end of a side member may be connected to a rear leg of the'invalid walker; FIG. 6 is a fragmentary side elevational view of an alternate joint structure for the juncture of a side member with a rear leg of the invalid walker;

FIG. 7 is a fragmentary front elevational `view of a second embodiment of the invalid Walker; Y-

FIG. 8 is a perspective view of a third emodiment of the invalid walker; and

FIG. 9 is a perspective view of a fourth embodiment of the invention. t

DESCRIPTION OF THE SELECTED EMBODIMENTS OF THE INVENTION The first embodiment of the invalid walker shown in FIGS. 1-5 comprises two side frames each of which vforms a forward leg and a rearward leg, the two side frames being interconnetced by a front frame that maintains the orientation of the two side frames relative to each other with substantial rigidity but nevertheless permits the side frames to rotate slightly in their planes for self-leveling of the walker, i.e. to permit simultaneously supporting contact of the four legs of the walker with a Hoor surface or ground surface even though the surface may be somewhat uneven or irregular. The whole structure comprising the two side frames and the interconnecting front frame is made of four U-shaped rod-like mem- -bers which may be, for example, extruded aluminum tubing.

Two of the tubing members, each generally designated 10, are of inverted U-shape and form the two opposite side frames, respectively, of the walker. Each of the tubing members 10 forms a forward leg 12 and a rearward leg 14, the two legs being connected by an upper intermediate portions which is provided with a yieldable sleeve 16 that serves as a hand grip for the user.

The other two of the four tubing members, which are generally designated 18 and 20 respectively, are U-shaped in plan with rearwardly extending arms. The forward intermediate portions 18a and 20a of the two U-shaped members 18 and 20 respectively, form the front frame of the walker and the rearwardly extending arms 18b and 20b of the two U-shaped members respectively are the previously mentioned lateral members that connect the two legs 12 and 14 of each of the two side frames at different levels and thus complete the two side frames.

In the first embodiment of the invention the forward intermediate portions 18a and 20a of the two U-shaped members 18 and 20, respectively, centrally cross each other and are interconnected at their intersection by a suitable fastening means 22 which may be in the form of a rivet. As indicated in FIG. 2, the two tubular members 18 and 20 may be at least slightly flattened for ntimate contact at their intersection.

The two tubular U-shaped members 18b and 2Gb may be connected to the two legs of each side frame in any suitable manner. In the construction shown, fastening members 24 positioned diagonally of the invalid walker extend through the 90 bends of the tubular members 18 and 20 into and through the front legs 12.

The rear ends of the two arms 18b and 20b of the two tubular members 18 and 20, respectively, may be connected to the rear legs 14 in any suitable manner. In the construction shown in FIGIS. 4 and 5, for example, each of the rear ends of the arms 18b and 20h is cut away or recessed to conform to the cross-sectional configuration of the corresponding rear leg 14 and is connected to the rear leg by a screw 26 and a pair of radially slotted dished disks 28 which are centrally apertured and internally threaded for engagement by the screw. The two disks 28 are dimensioned for forced fit and therefore expand radially into positive grip with the surrounding tubing when the screw 26 is tightened. Thus the end of each arm 18b or 20b in effect straddles the corresponding rear leg 14 to resist torsional forces that tend to rotate the arm relative to the rear leg.

FIG. 6 shows an alternate joint structure for connecting the rear end of a tubing arm 18a or 20b to a rear leg 14. The end of the arm 18b or 20b is bent downward at a right angle and the bent down portion is attened and rounded in cross section to straddle the rear leg. Two

screws 30 provided with nuts 32 rigidly connect the straddling portions to the rear legs.

Each of the four legs 12 and 14 may be constructed in a well known manner for adjustment in length to suit the user. For this purpose, the lower ends of the legs 12 and 14 telescope into short tubes 34. Each short tube 34 has a longitudinal series of radial apertures 35 as best shown in FIG. 8 and a spring-pressed detent member 36 with a rounded nose is retractably mounted in the lower end of each leg to engage the radial apertures selectively. Thus to change the effective length of a leg it is merely necessary to depress the rounded nose of a detent member 36 and then shift the tubes 34 to cause the detent member to snap into a different radial aperture. In a well known manner, the lower end of each of the short tubes 34 is provided with an elastomeric tip 38 for nonslipping engagement with the floor or ground.

It can be seen that by virtue of the intersection of the forward intermediate portions 18a and 20a of the two tubular members 18 and 20, the front frame centrally narrows to a minimum cross section at the intersection. This central portion 49 of minimum cross section may be termed a torque portion of the frame since the narrowed portion tends to yield in torque for the desired self-leveling action. In addition the four tube portions of the front that radiate from the torque portion may yield somewhat in flexure in the self-leveling action.

The high structural efficiency of the front frame may be appreciated when it is considered that the front frame comprises two triangular trusses that are integrally connected with each other at their apexes. It is well known that a triangle forms a perfect truss.

The effectiveness of the front frame in rigidly maintaining the two side frames at a constant orientation relative to each other derives from the fact that the front frame is integral with the tubular lateral members 18b and 2Gb that interconnect the legs of the two side frames. It is to be noted that the bends in the two tubular members 18 and 20 are formed with liberal radius for stiffness of the bends. The fact that the lateral members 18b and 20b that interconnect forward and rearward legs of the walker are integral with the front frame accounts in large part for the fact that slight loosening of an interconnection at any of the joints of the side frames does not result in any significant play of the two side frames relative to the front frame. Any diagonal downward force on either of the two side frames does not unduly distort the side frame because the two lateral members 18h and 20b of each side frame are integral with the front frame and thereby are effectively maintained in substantially horizontal positions.

The second embodiment of the invention, the construction of which is indicated by FIG. 7, is similar to the first embodiment in that it comprises four U-shaped tubular members. Two of the U-shaped members are the previously described U-shaped tubular members 10 which form the front legs 12 and rear legs 14 of the Walker, the other two-U-shaped tubular members which are designated 48 and 50 correspond to the tubular members 18, 20 of the first embodiment. The U-shaped tubular member 48 is an `upper member having a forward intermediate portion 48a and two rearwardly extending arms 48b that interconnect the side legs of the walker at a relatively high level. In like manner, the tubular member 50 is a lower tubular member having a forward intermediate portion 50a and two lower rearwardly extending arms 50b which interconnect the forward and rearward legs of the walker at a lower level. The forward intermediate portions 48a and 50a of the tubular members 48 and 50 that form the front frame of the invalid walker are V-shaped in front elevation as may be seen in FIG. 7, the two members 48a and 50a centrally converging together and being centrally interconnected by a pair of fastening members 52 to form a central torque portion 55 of the front frame.

It is apparent that the second embodiment of the invention is functionally equivalent to the first embodiment.

The third embodiment of the invention shown in FIG. 8 comprises four U-shaped members of the general character heretofore described. Thus each of the side frames that forms forward and rearward legs 12 and 14 comprises a previously described tubular member of inverted U-shape configuration. The second pair of U- shaped members that form the front frame of the invalid walker comprise an upper U-shaped member 56 and a lower U-shaped member 58. The forward intermediate portion 56a of the upper member 58 is substantially horizontal but the forward intermediate portion 58a of the lower U-shaped member 58 is offset to the configuration of an inverted V, the two front portions thus converging together and being centrally rigidly connected by a pair of fastening members 60 to form a central torque portion 62 of the front frame. The two rearwardly extending arms 56b of the upper tubular member 56 interconnect the front and rear legs of the two side frames at a relatively high level and the rearwardly extending arms 58b of the lower tubular member 58 interconnect the legs of the side frames at a lower level.

YThe two side frames are provided with the usual resilient hand grip sleeves 16 and the four legs are provided with the usual tubular extensions 34 and resilient tips 38.

It is apparent that the third embodiment of the invention is the functional equivalent of the first two embodiments. One advantage of the third embodiment over the first two embodiments is that with the torque portion 55 of the front frame at a relatively high level, there is ample room for the users legs to extend forward through the plane of the front frame.

FIG. 9 shows the fourth embodiment of the invention which is the functional equivalent of the other embodiments. This fourth embodiment comprises a first tubular member, generally designated 70, that is U-shaped in plan, a second tubular member, generally designated 72, that is also U-shaped in plan and two front straight leg members 74. The first tubular member 70 has a forward intermediate portion 75 and two rearwardly extending arms 76 that termin-ate in rearwardly downwardly extending legs 78 respectively. The forward intermediate portion 75 is the upper lateral member of the front frame and the two rearwardly extending arms 76 are provided with the usual sleeves 16 to serve as hand grips. The second tubular member 72 has a forward intermediate portion 80 and two rearwardly extending arms 82 which serve as lower lateral members of the two side frames and thus connect the forward leg member 74 with a rearward leg 78. The upper end of each of the leg members 74 is connected to the first tubular member 70 by suitable fasteners 84. It is to be noted that the forward intermediate portion 80 of the second tubular member 72 serves as the lower lateral member of the front frame and this transverse member is centrally offset upwardly and is connected to the upper lateral member 75 by suitable fasteners 85 to form the usual central torque portion of the invalid walker.

It can be seen that, in accord vwith the teaching of the invention, each of the two tubular members 70 and 72 that form the front frame of the walker is integral with two lateral members of the two side frames respectively to make the walker structure relatively rigid. It is also to be noted that the two lower rearwardly extending arms 82 have downwardly bent terminal portions 86 which are rigidly connected to the corresponding rear legs 78 by suitable fasteners 88. The lower ends of the four legs of the walker are provided with the usual adjustable short tubes 34 and the usual elastomeric tips.

The utility of the various embodiments of the invention may be appreciated by considering the fact that a basic problem in the construction of an invalid walker is to 6 provide adequate resistance to diagonal distortion or side sway, i.e. resistance to any force that tends to cause the walker to yield by leaning laterally in either direction. This problem is complicated by the fact that the rear of the walker must be fully open to admit the user and therefore the two rear legs cannot be directly interconnected across the back nor is any room available for bracing to extend diagonally from each front leg to the rear leg on the opposite side of the walker.

The invention solves this problem by two provisions which supplement each other. The first provision in all embodiments of the invention is to rigidly interconnect the two opposite front legs of the walker by a front frame that is structurally eflicient because it consists of two triangular trusses. A triangle is the only polyon whose shape cannot be altered in its plane Without changing the length of its sides. The second provision is, in effect, to wrap the front frame around the two sides of the walker by making the front frame integral with the side members of the two side frames at two different levels of the side frames. Thus leaning of the two front legs away from their normal positions is prevented by the exceptionally high resistance of the front frame to distortion in its plane and this resistance to leaning is effectively transmitted to the two rear legs by the rearwardly extending side members that are integral with the front frame.

It is important to note that while each of the two triangular trusses of the front frame effectively prevents distortion in its plane, nevertheless, since the two triangular trusses are interconnected at their apexes the front frame can be distorted out of its plane to a limited but useful degree by yielding in torque at the interconnected apexes.

The fact that the resistance to side sway of the two front legs is effectively transmitted to the two rear legs may be appreciated by considering the resistance to torsion of the rearwardly extending members of the two side frames. In the first three embodiments of the invention, each upper hand grip portion is integral with both the corresponding front leg and the corresponding rear leg and therefore offers high torsional resistance to lateral sway of the rear leg relative to the front leg. In all four embodiments of the invention the rearwardly extending arms at the opposite sides of the walker effectively resist torsion because they are integral with the rigid front frame of the walker and it is to be noted that each side arm is terminally rigidly connected to the corresponding rear leg of the walker.

Each of the four embodiments of the invalid walker is `of relatively simple construction in that it comprises only four tubular members. In the first three embodiments the four tubular members are U-shapedV either in plan or in side elevation. In the fourth embodiment two of the tubular members are U-shaped in plan and the other two tubular members are simple straight legs.

My description in specific detail of the selected embodiments `of the invention will suggest various changes, substitutions and other departures from my disclosure.

I claim:

1. In an invalid walker, the combination of:

two side frames, each providing two side legs of the walker, the two side legs of each side frame being interconnected by two side members at different levels; and

a front frame integral with the two side members of the two side frames, respectively, thereby interconnecting the two side frames and maintaining the two side frames at given orientations relative to each other, said front frame comprising two frame members that converge together centrally of the front frame, the convergent portions of the two frame members being interconnected to form a central torque portion of the frame that is sufficiently yieldable in torque to permit sufficient rotation of the two side frames relative to each other in their planes to permit the four legs ofthe walker to rest on a support surface and to conform to irregularities in the support surface in response to the weight imposed on the walker by the user.

2. A combination as set forth in claim 1 in which the front frame comprises two triangular trusses interconnected at their apexes, the interconnected apexes forming the central torque portion.

3. A combination as set forth in claim 2 in which the forward intermediate portions of the two rod-like members cross each other centrally and are interconnected at their intersection to form the torque portion of the front frame.

4. A combination as set forth in claim 1 which comprises:

a first pair of frame members of inverted U-shaped configuration in side elevation, each forming two side legs of the walker, the two side legs being interconnected by a hand grip portion of the frame member;

and a second pair of frame members U-shaped in plan having intermediate portions forming the front frame of the walker and having end portions interconnecting the legs on each side respectively of the walker.

5. A combination as set forth in claim 1 in which the ends of the two frame members are bent approximately 90 and extending longitudinally of the corresponding rear legs, said bent ends being flattened and rounded in cross section to conform to the rear legs, each of said bent ends being rigidly attached to the corresponding rear leg at points spaced longitudinally of the rear leg.

6. In an invalid walker, the combination of:

two side frames, each providing two side legs of the walker, the two side legs of each side frame being interconnected by two side members at different levels; and

a front frame integral with the two side members of the two side frames, respectively, thereby interconnecting the two side frames and maintaining the two side frames at given orientations relative to each other,

said front frame comprising an upper rod-like transnverse member and a lower rod-like transverse member, each U-shaped in plan with a forward intermediate portion and two rearwardly extending arms, the intermediate portions of the two rod-like members constituting the front frame of the walker and the rearward extending arms of the two rod-like members constituting the side members of the two side frames respectively,

said forward intermediate portions of the two rod-like members converging together and being interconnected centrally to form a torque portion of the front frame,

said upper transverse rod-like member being substantially straight and the lower transverse rod-like memcentral region of the upper rod-like member to form a torque portion of the front frame.

7. Inv an invalid walker, the combination of:

two side frames, each providing two side legs of the walker, the two side legs of each side frame being interconnected by two side members at different levels;l and a front frame integral with the two side members of the two side frames, respectively, thereby interconnecting the two side frames and maintaining the two side frames at given orientations relative to each other,

said front frame comprising an upper rod-like trans- -verse member and a lower rod-like transverse member, each U-shaped in plan with a forward intermediate portion and two rearwardly extending arms, the intermediate portions of the two rod-like members constituting the front frame of the walker and the rearward extending ar-ms of the two rod-like members constituting the side members of the two side frames respectively,

said forward intermediate portions of the two rod-like members converging together and being interconnected centrally to form a torque portion of the front frame,`

said upper transverse rod-like member being substantially straight and the lower transverse rod-like member being centrally offset to the central region of the upper rod-like member and being connected to the central region of the upper rod-like member to form a torque portion of the front frame,

the upper transverse rod-like member being centrally offset downward towards the lower transverse rod-like member, the lower transverse rod-like member being centrally offset upward towards the upper transverse member,

the two offset portions of the two transverse rod-like members being interconnected to form said torque portion of the front frame.

References Cited UNITED STATES PATENTS 2,627,904 2/ 1953 Thieman 135--45 X 2,798,533 7/1957 Frank 13S-45 X 2,852,145 9/1958 Schloz 182--179 X v 3,176,700 4/1965 Drury 13S-45 3,422,830 1/ 1969 Cherup 135-45 l FOREIGN PATENTS 1,249,691 ll/ 1960 France.

I. KARL BELL, Primary Examiner U.S. C1. X.R.

ber being centrally offset to the central region of the 297-5 upper rod-like member and being connected to the 

